Grate



H. K. MILNER Dec. 23, 1930.

GRATE Original Filed June 14, 1926 3 Sheets-Sheet l \0 INVENTOR ,9;H.H.Mazner ATTORNEYS WITNESS a4. aja u'm F K H. K. MILNER Dec. 23, 1930.

GRATE s sheets-sheet 2 Original Filed June 14, 192

INVENTOR H. H. M7, inc?" ATTORNEYS WITNESS Jw a.

H. K. MILNER Dec. 23, 1930.

GRATE ow WN 3 Sheets-Sheet 3 I: {I Illllllll Original Filed June 14,1925 llll lNvENToR H11. Mz-Zner' WITNESS ATTORNEYS Patented Dec. 23,19307 HENRY KEY MILNER, or

- 7 l Y on onennrsron,

BIRMINGHAM, ALABAMA, ASSIGN O R T MORTON KIRK MOORE, SOUTH CAROLINAsnare Application fil ed June 14, 1926, Serial No.115,928. RenewedNovember 7, 1930.

My invention relates to-improvements in grates for furnaces using coalor other'similarfuel, and it consists in the combinations, constructionsand arrangements herein described and claimed.

Anobject of the invention is the provision in a grate construction of anovel grate bar which will be relatively strong when madegof a givenamount of a given'material. f

A'furtherobject is a grate bar which includes a plurality ofinterchangeable quickly and easily and cheaply replaceable members ofsmall size and light weightforsupporting fuel within a furnace. '15 Afurther object of the invention is the provision in a grate constructionof a grate Afurther objectof the invention is the provision of agrateconstruction which per-- nuts practically unobstructed clrculation of amunderneath the fuel support ng elements of the grate, thus keeping themcomparatively cool and assuring relatively long-life, and" also permitsflow of air upwardly between the fuel supporting members of 1 the grateinto thefuelhed on the grate. V

A further object of the invention is the provision in'a grate of a novelgrate bar hav.

7 ing a'plurality off-fuel supportin'gmembers supported on a rockinglysupported bar and interlocked so that all air spaces between thesections willv have a predetermined constant width and so that all thefuel supportlng members on the bar Wlll move with the bar as a unit andeach of'said fuel supporting-members willheretained in place on therocking bar should such fuel supporting member be V c porting side bars4 which are adapted to exbroken; a V 1 A still further ob ect of theinvention is the provision in a grate of thecharacter described of anovel operating mechanism for rocking;

the grate bars inunison andnormally preventing-from dumpingtheburmngflfuel on the grate bars through the grate to a space below thegrate.

A still further object of the invention is the provision in a grateofmeans to cooperate with the grate bar operating mechanism toreleasably holdthe grate bar in position to maintain thegratesurfacelevel and to prevent the ends of the grate sections fromprojecting upward into the fire.

c Other objects and advantages of the invention will beapparent from thefollowing description, considered in conjunction with the accompanyingdrawings, in which Figure 1 is a horizontal section through the casingof a furnace equipped with a grate con struction embodying theinvention, the grate construction being shown in plan, 7 r V Figure 2 isa longitudinalverticalsection through the grate construction and throughthe adjacent portions of the furnace casing, Figure 3 is a section alongtheline 3 -3 of Figure 1,

Figure l of Figure 1, I V c Figure 5' is asection along the line 5'5 ofFigure l, 7 V

Figures 6, 9 and 11 ar similar fragmentary plan views of modifieu formsof fuel supporting members, of structions embodying the invention,

Figures 7, 10 and 12 respectively are end views of the structures shownin Figures 6, 9' and 11, respectively, and

isa section along the line 4-4 Figure 8 is a section along the line8-Sof Figure 6.

In Figures furnace casing having vertical side walls 1 and verticalfront and rear walls 2 and 3 respectively. The furnace casing per seforms no part of the present invention and may vary considerably inconfiguration and size from that illustrated in the drawings.

A. grate construction embodyingthe invention includes a pair ofstationary suptend along the innerfaces of the side walls ofthenassociate'd furnace-casing between grate bars used in con 1 and 2, Ishow a portion of a The upper edge of each of the side bars 4 is solid.continuous and unbroken and is substantially horizontal throughout itslength and the lower edge of each side bar 4 has upwardly otl'set endportions as indicated at la. Each side bar 1 may have the lower edgeportion thereof strengthened by a longitudinally extending rib 5 whichis continuous with the lower ed e portion of the side bar. T 1e sidebars 4 may be supported at their nds on masonry or other supports (notshown) or on the side walls 1 of the associated furnace casing bybracket hooks or lugs (not shown) which may be carried by the side wallsof the furnace casing and engaged with transverse notches or holes (notshown) at any points along the length of a side bar 4. A pair ofstationary end cross bars dead plates 8 is provided. Each cross bar 8has plurality of transversely spaced tongue extensions So at itsopposite ends adapted to fit in transverse notches 9 in the upper edgesof the end portions the side bars 4. The end cross bars 8 may beretained in place on the end portions of the associated side bars 4- byrod-like fastening devices 6 having upper end QOItlOllS extendingthrough vertical notches 10 in the end portions of the end cross bars 8and bent onto the side bars such fastening devices including hook-likelower end portions engaged with transverse notches 7 in the lower edgesof the end portions of the side bars at, whereby the ends of the crossbars will be securely tied or bound to the ends of the side bar".

A series of rocking grate bars is supported by the side bars 4 betweenthe end cross bars 8. Each rocking grate bar comprises a supportingcross member of bar-like formation having a body 12 which issubstantially rectangular in cross sectional configuration and which ispr vided at its opposite ends adjacent to its lower face with integralaligned trunnions 123. The body 12 of the supporting member of eachrocking grate bar spans the space between the side bars 4 and thetrunnions 13 are rockingly supported on the r.unded bottom portions 14of vertical slots .vhich extend transversely through the side bars atintermediate the upper and lower or ges of said ide bars. it

of course will be understood that the vertical slots are provided atregularly spaced intervals along each side bar l and that correspondingslots 15 of the two side bars 1 are in ali unent with each othertransversely of the furnace casing. Each vertical slot 15 is enlargedlaterally in opposite directions its upper end, thus producing thebranch slots 16 which er end longitudinally of the side bar a inwhichthey are former. The supporting member 12 of each rocking grate baris placed in position to be supported by the cross bars by placing thetrunnion 13 a one end of said supporting member in the correspondingslot 15 in one of the side bars and then tilti g the supporting memberuntil the trunnion 1?) at the opposite end of said supporting member canbe moved from one of the lateral branch slots 16 into the associatedslot 15 and then down "ardly to position to rest on the portion 14 ofsaid vertical slot, at which time said supporting member of the rockinggrate bar assen'ibly will be horizontal.

The side bars 41 are formed with pairs of intergral 111 's 17 on theirinner faces, the respective lugs 17 of each pair being located adjacentto and at opposite sides of the lower end portion of a slot 15, therebeing a pair of the lugs 17 for each slot 15. The lugs 17 of each pairconstitute stops for limiting the rocking movements of the supportingmembers of the grate bars about the axial lines of the trunnions 13 andthe upper faces of the lugs 17 are inclined outwardly and upwardly withrespect to the associated slots 15 so that a side face of the supportingmember 12 will rest fiatwise on the upper face of an adjacent lug 17when said supporting member has been rocked in either of oppositedirections about the axial line of its trunnions 13.

Each of the supporting members 12 is provided at regularly spacedintervals along its length with vertical sockets 18 which arenon-circular in cross section and may be rectangular in cross section asshown. The sockets 18 are adapted for the reception of correspondinglyconfigured shanks 19 of replaceable and interchangeable fuel supportingmembers which include the fuel supporting head portions 20 at the upperends of the shanks 19. The fuel supporting heads 20 are substantiallyelliptic in elevation with slightly extended end portions at theopposite ends of the elliptical transverse openings 21 which thus areproduced in the heads 20. Each of the opposite ends of each fuel supporting head 20 is provided with oppositely extending lugs and 81respectively. The lug 80 is provided with a vertical notch 80a in itsextremity and the lug 81 is provided with an extending tongue portion81a at its extremity adapted to enter and engage with the notch 80a atthe corresponding end of the adjacent head member 20, whereby theinterlocking engagement of the lugs on adj acent head members of thefuel sup 'iorting members will assure proper positioning of the fuelsupporting members at all times and the air spaces between the fuelsupporting members will have a constant predetermined width. The fuelsupporting heads 20 thus have relatively great strength when formed of agiven amount of a given material and permit complete circulation of airaround every part of each fuel supporting head so that it v ll be keptcool and its life thus prolonged. The shanks 19 depend from the centralper-- tions of the heads 20. As hereinbefore iii stated, the lower faceof each of the supportmg cross members 12 of a rockinggrate bar assemblyis inclined downwardly from its opposite ends toward its transversemedian line and since each of the members'12 has thelspaced verticalsockets 18 formed therein to extend vertically therethrough,the-supporting cross member of e'achrocking grate bar may be said tobeof double trussed design and thereforewillbe relatively strong for theamount of a given material that is used in its construction.

A pair of shaker hooks 22 is'provided for each of the rocking grate barassemblies. As shown to advantage in Fig. 5, the respective hooks 22 ofeach pairhave their shanks disposed vertically at opposite sides of themember 12 of the associated rocking grate bar so i that the billportions'22a of the hooks will extend transversely across the upperfaceof the associated member 12 from opposite of hooks 22 will be firmlyclamped to the associated member 12 between ad acent fuel supportingheads 20-when the lower end portions of the shanks ofthehooks,'whichover-1 lap underneath the longitudinal median line of the associatedmember-:12 as indicated .at

24 in Fig. '5, are connected by a transverse fastening element 25 whichextends through aligned openings? in the lapped'lower' end portions ofthe shanks of the hook members 22. 1A shaking bar is connected with thelapped lower end portionslof the ishanksof the shaker hooks andtmaycomprise a pair.

of'bar like sections 26whichstraddlethe lapped lower en'dportions of theshanks of the shaker hooks and are pivotally attached to said shakerhooks and thus connected with each other bythe same fastening element25.

that is used to connect-the lower: end fportions, of the shanks oflthejpair l of shaker V l1ooks=.: The shakerbar sections 2 6.'are ofsufficient 1 length to [straddle the connected to-' gether portions ofthe pairsofshakerhooks for all the rocking grate bar assemblies. A

couplingmember'27;extends through an aper- I ture 28 which maybe the ashdoor opening in thefront wall 2 of the furnace casing.beloiv the usualfuel feed .opening not shown; fiThe inner end portion of the coupling{member 27 is straddled by the forward end portions of the sections ofthe. shaker bar and iscon nected with the sections of the shaker bar byva horizontal pivot element 29 which'may be theshank of abolt thatis.retameclin place in aligned transverse openingsin the lapped portions ofthe sections of the barand the coupling member by means of a nut 30. The

outer end portion of the coupling member 27 is formed to produce 'a pairof vertically spaced forks 31,-thusdefining a horizontal slot 32 for thereceptionofan endportion of an arm 33 of ahorizontally disposedsubstantially right angular bell crank lever 34. The lapped portions ofthe bell-crank lever arm 33 and theforks 31 of the coupling member 27are connected by a vertical pivot element35. The bell-crank lever 34includes an 7 arm 36 and ahub portion 37 at the juncture of the arms 33and 36 of the bell-crank lever. A bracket 38 may be attached to thefront wall 2 of the furnace casingat either side of the usual ash dooropening without any change or reversal of any kind by rivets39' or likefastening'devices, and has a pair of forwardly extending verticallyspaced hori- V zontal arms 40 and 41 respectively between which the hub37 of 'the bell-crank lever is disposed and to which the hub of thebellcrank lever-is connected by means of a vertical pivot element 42. vThe bell crank lever may be used at either. side of .the ash door.opening simply by turning the bell crank lever so that the arm that'isto be connected the shaker bar will extend eithertothe right or totheleft of the. bracket, this being determined by the location of thebracket relatively tothe ash door opening. As clearly shown in Figure 4,the lateral edge portions of the bracket arm 41 extend beyond thelateral edges of the bracket arm 40, thus producing horizontal ledges'at43 and providing a bearingsurface of relatively great area for thetop-of the.

bell-crank lever. ,The ledges 43 also have anotherfunction to bepresentlydescribed. The

extremity of the arm 36 of .the bell-crank is convexly' curvedl invertical section as indicated at 43. An operatingorshaker handle bar44-hasan undercut longitudinally extend,

ing slot45 in its inner end portion for the;

reception of the outer end portion of the-bellcrank lever arm 36. Ahorizontal pivot ele-,,

ment 46 extends through the sidewalls of the slot 45'and' through theouter end portion of the bell-crank lever arm 36, whereby the handle 44.will be connected with the arm 36 no i of the bell-crank lever so thatthe handle 44.

may swing fromthe dottedline position of Figure 3 tothe out-of-the-wayposition shown by the full lines of Figure 3. When the han dle44 isinthe position shown by the dotted lines in Figures 3 and 5, bodilymovement of" the handle 44 in a horizontal plane will cause thebell-crank 34 to, be rocked horizontally about the axis of the pivotelement 42, and

motion will be transmitted from the bellcrank lever through the"coupling member 27 to theshaker bar and thence to all the rocking gratebar assemblies which will be rocket simultaneousl The bell-crank levermay.

be locked to the bracket 38 to prevent accidental rocking of the rockinggrate bar assemblies when such assemblies are in position to maintain alevel bed of fuel thereon. This locking of the bell-crank lever to thebracket may be effected by placing a latching pin 47 in a verticalaperture 48 in the arm 36 of the bell-crank lever so that the endportions of the pin 47 will enter and engage with vertically alignednotches 49 and 50 in the ends of the bracket arms 40 and 41,respectively.

The extent of rocking movement of the bell-crank 34 about the axis ofthe pivot ele ment 42 and therefore the extent of rocking movement ofthe rocking grate bar assemblies may be limited by stop shoulders 51 and52, respectively in the edge of the hub portion 37 of the bell-cranklever adjacent to and at opposite sides of the body of the bracket 38.\Vhen the rocking grate bar assemblies are in position to maintain alevel grate surface in the fire box of the furnace, the bell-crank leverwill be in the position shown in Figure 1 and it will be observed'thatthe stop shoulder 51 on the bell-crank is nearer to the adjacent sidewall of the body of the bracket '38 than the shoulder 52 to the otherside wall of the bracket 38. In order to prevent rocking of the rockinggrate bars from the positions shown in Figure 1 to the positions to dumpthe fuel bed through the spaces between adjacent grate bars, theinvention provides a substantially right angular latch bar 53 whichincludes a relatively long arm attached by a horizontal pivot element 54to the front wall of the furnace casing at one side of the bracket 38 sothat the other and shorter arm of the latch bar may be swung about theaxis of the pivot element 54 to and from position to rest on theadjacent ledge 43 of the bracket between the front wall of the furnacecasing and the shoulder 52 on the bell-crank. The shoulder 52 then willengage with the end of the shorter arm of the latch bar 53 or theshoulder 51 will engage with the adjacent side wall of the body of thebracket 38 for the bell-crank lever can be rocked about the axis of thepivot element 42 to an extent sufiicient to cause the fuel on therocking grate bars to be dumped through the spaces between adjacentrocking grate bars. However, the rocking of the grate bars when thelatch 53 is in operative position will be sufficient to permit desirableshaking of the fuel bed. Vhen it is desired to dumpthe fuel bed throughthe grate assembly, the latch 53 is swung upwardly from the position ofFigure 1 and the full line position of'Figure 4 as indicated by thedot-ted line position of Figure 4 and the bell crank lever then may berocked until the shoulder 52 strikes the adjacent side wall of the bodyof the bracket 38 and the rocking grate bars may be rocked about theaxial lines of the trunnions 13 until thesupporting member 12. of eachgrate bar is in contact with one of the lugs 17 and as required to causethe fuel bed to be dumped through the grate.

From the foregoing description of the various parts of the device, theoperation thereof may be readily understood. ,VVhen the fuel supportingmembers shown in Figures 1, 2 and 5 are used, the vertical sockets 18 inthe bodies of the supporting cross bars of the rocking bar assembliesare all used for the reception of shanks of fuel supporting headmembers. Adjacent sockets 18 are spaced apart at such a distance thatthe side faces of adjacent fuel supporting heads of the grate barassemblies will be adjacent each other. It will be observed that a spaceis provided underneath the fuel bed supporting heads for the circulationof air so that the parts of the grate bar assemblies which are incontact with supporting members will not be unduly heated and the gratebar assemblies therefore will not be likely to be broken or to requirereplacement frequently. It will be observed that the direction of lengthof the fuel bed supporting head members of the grate bar assemblies issubstantially parallel with the side walls of the furnace casing and atright angles or substantially at right angles with the front wall of thefurnace casing so that these head members will not be damaged or brokenby the impact of a poker or like tool that may be used to break up thefuel bed.

If desired, I may make use of fuel supporting members in the grate barassemblies of the type which embraces all the forms of fuel supportinghead members shown in F igures 6 to 12 inclusive. It will be observedthat the form of fuel supporting head member shown in Figures 6 and 7includes a shank 19a which is identical in essential respects with theshank 19 of the fuel supporting head member shown in Figures 1, 2 and 5.The head portion of the fuel supporting member shown in Figures 6 and 7is indicated at 20a and has the same general configuration inlongitudinal vertical section as the head member shown in Figures 1, 2and 5. However, the head 20a of the member shown in Figures 6 and 7 hasa width approximately twice that of the head 20 of the fuel supportingmembers shown in Figures 1, 2 and 5 and is provided at opposite sides ofeach end portion thereof with an extending lug having a tongue portionand a lug having a vertical notch 61. The respective tongue portions 60and the notches 61 at opposite ends of the head portion 20a of the fuelsupporting head member shown in Figures 6 and 7 are at opposite sides ofthe head portion 20a of that fuel supporting head member and each tongue60 or notch 61 is adapted to engage with the notch 61 or tongue 60 ofthe adjacent fuel supporting head member no matter how these gratesections and the interlocking connections on IOU them are dropped intoplace. The respective 7 only every other socket 18 in the supportingcross member 12 of a rocking grate bar assembly is used for thereception of a shank 19a of each of the fuel supporting members 20a andthe fuel supporting members 20a on one of the members 12 will be lockedto one another so as to form a substantially rigid construction byreason of the engagement of the tongues on each fuel supporting headmember with the notches 61 inthe adjacent fuel supporting head members.In addition, the head portion of each of the fuel supporting members 20amay be provided with a longitudinally extending vertical aperture 62 inthe crown portions thereof, which as hereinbefore stated, issubstantially twlce as wide as the crown portion of the fuel supportinghead member shown in Figures 1, 2 and 5.

The fuel supporting head member shown in Figs. 9 and 10 has the shank19b and a head portion 206 which difiers from the head portion 20a ofthe form of fuel supporting member shown in Figures 6 and 7 only in thatthe head portion 20?) has three relatively narrow parallel slots 62a inthe crown portion thereof. The fuel supporting head member shown inFigures 11 and 12 has a shank 190 and a head portion 200 which differsfrom the head portions 20a and 206 only in the number of longitudinalslots which are formed in the crown portion thereof, there being twolongitudinal slots indicated at 625 in the crown portion of the headmember shown in Figures 11 and 12.

The fuel supporting headmembers shown in Figures 6, 9 and 11 may be usedinterchangeably and the fuel supporting head members shown in Figures 6,9 and 11 may be substituted for the fuel supporting head members shownin Figures 1, 2 and 5. The' fuel supporting members shown in Figures 6,9 and 11 have exactly the same number of square inches of grate surfaceand fit in exactly the same manner into the sockets of a rocking crossmember, the only difference being that the head member shown in Figure 9has an air space wide, the head member shown in Figure 11 has an airspace wide, and the head member shown in Figure 6 has an air space A!wide. This variation in the width of the opening for draft or air adaptsthe grate forthe use'of coal of ordinary size, very small size, or slackcoal. At the same time, the diflerent fuel supporting members areinterchangeable with one another'an'd in an emergency can be mixedindiscriminately in the same grate assembly. This is an importantadvantage in the practical operation of the grate. It thus will beobserved that I have standardized the parts of the improved grate,construction which are next to the fire and which are the only parts ofthe grate construction that are likely to require replacement as aresult of the requirements of ordi- V nary service. All. parts of theimproved grate construction are relatively strong and light in weightand can be manufactured at relatively low cost, thus making for economyin the cost of installation and maintenance.

I claim:

1. In a fuel supporting element for grates,

an elliptical shaped head having a transverse opening extending entirelytherethrough and a vertically disposed slot extending substantially thelength of the head and stopping short of the ends of the latterandcommunicating with the transverse opening, a horizontal support, and ashank projecting from the under face of the head for supporting thelatter on said horizontal support.

2. In a fuel supporting element for grates, a substantially ellipticalshaped head having a transverse passage which opens at the oppositevertical faces of the head and further provided with a longitudinal slotin its upper face having communication with the transverse passage, ahorizontal support providing a socket, and a shank depending from theunder face of the head to be received in the socket of said horizontalsupport.

3. Ina fuel supporting element for grates, a substantially ellipticalshaped head having a transverse passa e which opens at the oppositevertical facesof the head and further provided with a longitudinal slotin its upper face having communication with the trans verse passage, ahorizontal support providing a socket, and a shank depending from theunder face of the head to be received in the socket of saidhorizontalsupport, and oppositely extending V-shaped lugs formed on the oppositeends'of the head adapted for interlocking engagement with similar lugsof an identical fuel supporting element whereby to hold two adjacentfuel supporting elements against relative longitudinal shifting.

HENRY KEY MILNER.

